Okay, second attempt to create a simple-ish Venn diagram showing the major SF subgenres! This one might be closer to accurate!
As you will see, I expanded the “Adventure” circle tremendously and overlapped everything else into that specific circle — but as you can also see, I decided that some SF novels are actually outside that circle for multiple subgenres. Now that I’ve copied this diagram and dropped it into this post, I can immediately see some things I might have done differently, BUT, look! I have nudged Space Opera so that a bit of the circle lies outside Adventure SF! I didn’t realize I was going to do that because I usually think of Space Opera as necessarily emphasizing adventure (and high stakes and so on), but creating these diagrams has made me see that I don’t really think that. Because I do think Long Way is space opera, and it can just barely be called Adventure; and where exactly would you put Nathan Lowell’s Quartershare? It’s totally adventure-free! There are basically no stakes whatsoever! But then where would you put it? It doesn’t fit anywhere else! I finally chose to drop it into the Space Opera circle, but outside the Adventure circle.
I put Sharon Shinn’s Archangel outside the Adventure circle too. Sure, stuff happens; yes, some of that stuff involves action and excitement, but it’s basically a romance story. Excitement and adventure are not the point. The romance is the point. It’s not an adventure story! Not sure I should have placed Pern in the same location; maybe that is actually more of an adventure story? But maybe not, maybe it’s in the right place.
Cyteen isn’t really Adventure, but the sequel, Regenesis, is DEFINITELY not adventure. It’s like a tiny, tiny bit of excitement got added as a sort of nod to reader expectations, but it’s not at all about that. It’s about everyone getting their lives in order. I really liked it! So I dropped Cyteen on one side of the Adventure line, Regenesis on the other, but if someone wanted to put Cyteen outside the Adventure circle as well, I wouldn’t argue.
I tried hard to get Near Future, Far Future, and Cyberpunk to all overlap with Sociological SF, but I just couldn’t get them all to fit and finally decided that when you’ve gone that far into the future, you’re not likely to be handling sociology at all realistically, so I let that one shift away from Sociological SF. I dropped Psionics as a circle and put Psion in the SF Fantasy circle, because I do think psionics should by all rights be considered fantasy. This element just often comes with SF trappings, like time travel.
I decided I agree that No Foreign Sky isn’t Military SF and moved it out of that circle, but put it in the Space Opera circle. I kept Invictus outside the Space Opera circle. Both wound up in the Sociological SF circle. To make a more clear distinction between various novels that are all Military SF, I dropped A Small Colonial War into a different section of the Military SF circle than Honor Harrington. That one, Quartershare, and Regenesis are the ones that are new to this version of the Venn diagram. I really liked both A Small Colonial War (Robert Frezza) and Quartershare (Nathan Lowell), by the way. The former isn’t available in ebook form. None of Frezza’s books are available as ebooks. Who published them? Oh, Del Rey. Well, it’s a real shame Del Rey hasn’t seen fit to make its backlist books available as ebooks. I like this whole trilogy a lot. I like Lowell’s series a lot too, and Quartershare in particular is certainly one of the lowest-stress novels you can possibly read.

I hardly think this diagram is definitive, but I’m kind of happy with it! On the other hand, now once again I don’t know what I think Space Opera actually is! I still disagree with the “Westerns in space” idea — that fails to capture The Long Way, Quartershare, Chanur — I just think it misses a lot of books that to me seem to belong in this category. Maybe I should throw up my hands and declare that the term is useless and I know it when I see it?
Which elements do you all think are largely, if not entirely, universal for Space Opera?
- Set in space, aboard spaceships
- SF elements not particularly “hard” — handwavy SF elements are fine
- Adventure is a central component of the story
- High stakes that keep rising
- Battles, maybe an ongoing war
- Fast pace
- Tone not gritty
- Tone actually heroic, cheerful, or positive in some other way
- If there’s conflict, the good guys win
- Some characters may belong to military organizations, but the story does not involve details about daily life in the military
Before all this discussion, I would probably have voted for ALL of these characteristics. Now I’m not sure! I think the above list is characteristic of A LOT OF Space Opera, but maybe not all of it? Or should Quartershare be placed somewhere else? If it should, where? Am I missing a whole circle?
I’d still move the Far Future circle outward, so that it overlaps with SF Fantasy and also exists partly outside everything else — one of the ur-texts is Olaf Stapledon, who’s not only not adventure but is barely written like fiction. And I don’t know of any overlap between milSF and Far Future, though it woudn’t shock me if there’s some that technically counts.
For Quartershare, the problem is that there isn’t a term for its subgenre, which you could call lslice-of-life or coming-of-age — huh, maybe YA as a circle? With all or most of the Heinlein juveniles in its large overlap with Adventure SF. Or, taking a leaf from one of your posts a few weeks back, we could announce the existence of Cozy SF.
Craig, you know, Cozy SF is obviously the right subgenre for Quartershare, and I don’t know why I didn’t think of that.
Ooooh. I’m going to have to look up “Quartershare”, because I have never heard of it and ADORED “The Long Way to a Small, Angry Planet”. If they’re that close on your diagram, I’ll probably like it. (By Nathan Lowell, right?)
I liked “No Foreign Sky” as well; maybe I should also investigate “Chanur”…
Heather, Quartershare is not a lot like The Long Way. It’s pleasant. It should indeed be in a circle labeled “Cozy SF.” The protagonist is too good to be true, but hey, sometimes that’s exactly what I’m in the mood for. The sequels have a little more plot to them but are still low-tension and pleasant.
Another overlapping category could be SF mystery. I can think of a few LMB books that would go in that circle